Focusing device for lamp bulbs



Jan. 31, 1928. 1,657,500

H. C. FOSTER v FOCUSING DEVICE FOR LAMP BULBS Original Filed Nov. 24, 1925 INVENTOR. fi/mrr C! Fears/e.

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Patented Jan. 31, 1928.

UN T STATES PATENT oFFics."

PORA'ITION, or oon EnsvI Ln, INDIAN a CORPORATION.

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Original application filed November 24,1925, serial No. 71,102. Divided and this application meg Jul 2. 192s. Serial in). 120,010.

This invention pertains to v a headlamp structure, particularly "that type employed in connection with automobiles and similar vehicles. i

The feature of the invention resides in the mounting of the lamp socket for permitting the lamp to be vertically adjusted for focusing as well as longitudinally adjusted.

This application is a division of application Serial No. 71,102, filed November 2 1, 1925.

The full nature of the invention will be understood from the accompanying drawings and the following description and claim.

Fig. 1 is a central vertical section through the lamp structure. Fig. 2 is a rear elevation of a part thereof. Fig. 3 is a section taken on the line 33 of Fig. 1. Fig. t is a section taken on the line t-t of Fig. 1. i In the drawings there is shown a lamp structure embodying the casing 10, the retiector 11, lens 12 and door rim 13 and lamp 1 1. The casing 10 is provided with the usual head 15. Extending through the flanged face 16 preferably at the top of the lamp, there is a stem 17 having a hook portion 18 on the inner end thereof in position to hold the compression spring 1.9 surrounding the stem intermediate the end thereof and the flange 16. The stem 17 terminates in a plate 20 having the slot 21 in which the hook 22 mounted on the door rim 13 may engage. Extending through the flange 16 of the casing on the side thereof diametri cally opposed to the plate 20 there is provided a similar stem 22 extendingthrough said flange and surrounded by the springs 23. The head of the stem 22 is bent over to provide an internally screw threaded nut 24 which will lie adjacent an opening in the door rim which is adapted to register therewith when the rim is hooked into the plate 20.

The position of the reflector 11 intermediate the flange 16 of the casing and the lens 12 which is secured within the door rim is such that when the door rim is hooked into the plate 20 the lower side thereof will extend outwardly at an angle due to its fulcrum-like engagement with the reflector. The outwardly extending lower side of the door rim. may then be forced inwardly against the reflector as a fulcrum point, COIHPIQSSIHg the spr1ng19 sothat thescrew 25 may be screwed into the nut 24 and hold it under spring tension against the.

reflector 11 through the medium of the lens and packing.

The bulb 1 1 is mounted in the usual bayonet slotted sleeve secured to the forwardly projecting arm of a U-shaped threaded bar 31. Said bar is supported by the screw bolt 32 having a head 33 so that as said bolt is rotated from the exterior of the casing, the lamp 14 will be moved axially of the reflector for focusing purposes. Intermediate the head 33 and the rear surface of the casing there is provided a rearwardly bulged plate 3 1- against which the screw head bears, and against the inner surface of the casing there is a similarly bulged plate 35 held in place by the spring 36 intermediate said plate and the bar 31. The intermediate portion of thecasing is slotted and a similar slot 37 is formed therein immediately below the same. The plates 34 and 35 are each provided with cars 38 and 39 respectively overlapping the slot 37 through which the screw 40 extends for clamping said ears together. By means of this arrangement, upon the screw 40 being partially unscrewed so as to release the clamping engagement of the ears 38 and 39, both plates 31- and 35 may be moved up or down carrying the bulb 14 therewith for adjusting the same in a vertical plane or transversely to the axis of the reflector. This is accomplished without affecting the screw 32 owing to the spring-like eflect of the bulging plates. On the other hand the adjustment of the bulb longitudinally of I of, a reflector mounted therein, a door c10- snre therefor, a bulb positioned in said reflector, a pair of spring plates mounted on each side of said casing and embracing the opening therethrough, said plates being provided with bulged surfaces extending away from each other and the casing whereby the centers thereof will be substantially spaced apart, radially extending ears formed thereon, a bolt extending through the bulged portion of said plates which will provide supporting bearing therefor, a bulb supporting member screw threaded on said bolt for permitting adjustment of the bulb longitudinally of the axis of the reflector, a compress-ion spring mounted between said menr her and the inner plate for resiliently holding said bolt in position axially of the re flector, and a second bolt extending through the ears of said plates and theopening in said casing for frictionally clamping said plates against sliding movement opposite said casing, and permitting sliding movementthereof when loosened for adjusting the bulb in a plane at right angles to the axis through the reflector.

In witness whereof, I have hereunto affixed my signature.

HARRY (ll. FOSTER. 

